Patent GB-114960-A (GB)
IPC: A43D27/00
Abstract: 114,960. Dehn, F. B., (Alsop Process Co.). Aug. 20, 1917. Lathes.-Consists of a machine for cross-cutting leather logs to form bootheel blanks in which a knife or knives is rotated around and at the same time moved inwards towards the axis of the log while this is held stationary. The log 8 is clamped in a holder, comprising a trough-shaped member 9, and a bar 10. the forward end of which passes through a continuously rotating sleeve 7 mounted in bearings 6 and carrying a spur-wheel 86 which gears with a wheel 85 on the main shaft 2. The forward end of the sleeve is formed with a flange 51 against which is placed a loose spur-wheel 54 in gear with a wheel 87 which may be coupled to the shaft 2 by a friction clutch, the driving-member 89 of which is fixed to the shaft. The shaft is movable endways in its bearings; normally it is pressed to the left to keep the clutch in action by the spring 95, rod 92 and lever 91; it is periodically shifted to uncouple the clutch by means of a ram 79 on the wheel 78 making contact with a roller 99 mounted in a stationary support. The knives 64 work in proximity to the end of the holder and are fixed at each end in curved arms 62 which are pivoted on studs 52 secured in the flange 51; the tails 60 of the levers are connected by links 71 to pins 72 secured in the spur-wheel 54 the face of which has slots 56 for the passage of the studs 52. The gearing is so proportioned that the sleeve runs slightly faster than the wheel 54; thus during a cut the studs 52 move from the rear ends to the front ends of the slots and the links 71 push out the tails of the arms, thereby causing the knives to move inwards towards each other. Upon the completion of the cut the clutch is disengaged leaving the wheel 54 free. whereupon it is drawn forward by a spring to overtake the sleeve and the knives are moved outwards clear of the log which is then fed forward ready for the next cut. The part 9 of the holder is supported on an adjustable bracket 11 and an adjusting-screw 12; the part 10 is supported upon it by a pair of links 25 which engage the ends of a pin 23, passing freely through the member 10, and are pivoted to the forked end of a lever 15 which is pivoted on the underside of the part 9 and bears centrally by means of a projection 20 on the fixed frame of the machine. The arrangement provides for the simultaneous adjustment of the top and bottom members to suit the size of the log to be treated. The rear end of the part 10 overbalances the forward end so that it tends to move out of clamping engagement with the log; it is pressed into engagement by a pair of levers 33 mounted on the ends of the pin 23 and controlled by a spring 40 in such a manner that a bar 46 uniting the upper ends of the levers is pressed against the projection 21 of the part 10. When the shaft 2 is moved to the right the grip is relieved by the action of a collar 40 on the shaft upon a sleeve 30 connected to the levers. The feed is then effected by a set of pivoted serrated dogs, pressed by springs against the sides of the log, which are mounted in a slide 105 operated by the lever 101 and the cam 82 on the wheel 78. The slide is retracted by a spring 111 and backward movement of the log is prevented by a dog 120 pivoted in the member 10. A modified construction of knife is described; this consists of a blade in the form of a quadrant secured along its curved edge to the lever 62.